Thread: Stabilizing robot on bridge with gyro or accelerometer
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Unread 16-01-2012, 08:02
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FRC #0254 (The Cheesy Poofs), FRC #0341 (Miss Daisy)
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Re: Stabilizing robot on bridge with gyro or accelerometer
I think that even a PD controller on the gyro may be overkill in this application. When we were trying to balance one or more robots manually on our ramp, we found that our drivers essentially implemented the following algorithm:

1. Start creeping up the ramp
2. Keep going until the ramp has begun tipping
3. Stop and/or reverse by a pre-specified distance

We found that putting your drive speed controllers in "brake" mode (or alternatively, using a drive PID controller that prevents rolling when the driver backs off the throttle) is essential.

Our ramp (being of the home-made variety) is much more sensitive than the competition ramp, but this basic approach seems like it works pretty well. The ramp has a fairly stable balance point; you just need to get it there!